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From 7 naturally occurring Nd isotopes, 5 are unstable in relation to α decay. If an excited level of the daughter nucleus is populated, or the daughter nucleus is unstable, γ quanta can be emitted. We used an ultra-low background spectrometry system with 4 high purity germanium (HPGe) detectors (about 225 cm3 volume each) to search for such decays using a highly purified Nd-containing sample with mass of 2.381 kg. Measurements were performed at the INFN Gran Sasso underground laboratory (with an overburden of about 3600 m w.e.) during 51,237 h. Half-life limits for α decays of 143Nd and 145Nd were determined to be T1/2(143Nd) > 1.1 × 1020 year and T1/2(145Nd) > 2.7 × 1019 year at 90% C.L. This is an increase of three and two orders of magnitude, respectively, compared with the most restrictive values currently given in literature. A limit for α decay of 144Nd to the excited level of 140Ce with Eexc = 1596.2 keV was determined for the first time as T1/2(144Nd → 140Ce*) > 9.3 × 1020 year. Restriction for the α decay of 146Nd to the excited level of 142Ce with Eexc = 641.3 keV was increased by 3 orders of magnitude to T1/2(146Nd → 142Ce*) > 1.4 × 1021 year. For α and 2α decays of 148Nd, first T1/2 limits were set as 4.2 × 1018 year and 2.1 × 1020 year, respectively. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of different design parameters on the low-temperature crack resistance of recycled asphalt mixtures and to provide design guidance for recycled asphalt mixtures. Three material composition factors (reclaimed asphalt pavement (RAP) content, gradation type, and asphalt content) and four mixing process factors (RAP preheating temperature, mixing duration, mixing temperature, and mixing sequence) were considered. Using a single-factor controlled variable method, AC-20 recycled asphalt mixture was designed to study low-temperature crack resistance through a semi-circular bending (SCB) test, the significance of the effects of different factors was analyzed using the orthogonal test, and the fracture surface morphology was observed. Results show that both material composition and mixing processes impact the low-temperature crack resistance of recycled asphalt mixtures. Specifically, lower RAP content, higher asphalt content, higher mixing temperature, longer mixing duration, and mixing sequence I favor improved low-temperature crack resistance. Gradation type and RAP preheating temperature showed non-linear effects, peaking before declining. Material composition, especially asphalt content, has a more significant effect on the low-temperature crack resistance than mixing process factors. To achieve optimal low-temperature crack resistance, it is recommended to optimize the material composition of recycled asphalt mixture and control the RAP preheating temperature to 110 °C, maintain laboratory mixing duration of at least 150s, set the mixing temperature to at least 160 °C, and follow mixing sequence I. [ABSTRACT FROM AUTHOR]

Natural filler-reinforced PLA composites are a sustainable alternative to petroleum-based polymers in industries such as automotive, consumer products, packaging, aerospace, sports, and electronics. However, they have poor performance in humid environments due to the hydrophilic nature of fillers. Graphite is an effective reinforcement to improve the strength and hydrophobic nature of composites. Therefore, this study explores the effects of reinforcing graphite (5–20%) on the properties of PLA composites reinforced with waste sawdust (10–30%). The mechanical, thermal, and water absorption properties of injection mold samples are evaluated following ASTM standards. The mechanical and thermal properties of graphite-reinforced composites outperformed those of neat PLA and sawdust-reinforced composites (SDC) due to their higher rigidity, thermal conductivity, and nucleation effect on the composites. HC2 (10% graphite) achieves peak tensile and flexural strengths of 54 and 145 MPa, surpassing PLA by 237.5 and 241.2%, and SDC by 10.6 and 25%, respectively. Furthermore, peak compressive strength and hardness of 82.33 MPa and 84 are obtained for HC2. However, excessive graphite reduces the impact strength of HCs due to stress concentration and brittleness. The crystallization and thermal stability are also improved due to the nucleation effect of SD and graphite in the HCs. Moreover, the water absorption of HCs is lower than that of SDC by 9.2–32.7%, indicating the effectiveness of hydrophobic graphite reinforcement. The measured results reveal that the addition of graphite as secondary reinforcement in HCs enhances the mechanical and thermal properties of the composites while reducing water absorption. [ABSTRACT FROM AUTHOR]

Hybrid flow shop (HFS) environments are prevalent in various industries, including glass, steel, paper, and textiles, posing complex scheduling challenges. This paper introduces a novel approach employing Variable Neighborhood Search (VNS) to address the HFS scheduling problem, with a primary focus on minimizing makespan. The fundamental innovation lies in the fusion of VNS with domain-specific strategies, harnessing the adaptability of VNS. Departing significantly from conventional HFS approaches, our methodology incorporates a special encoding that allows jobs to wait strategically, even when free machines are available. This approach trades immediate machine utilization for the potential of improved makespan. Additionally, using this encoding, a proper decomposition of the problem is feasible. This innovative strategy aims to balance machine load while optimizing the overall scheduling performance. Experimental testing demonstrates the effectiveness of the proposed approach in comparison to existing methods. [ABSTRACT FROM AUTHOR]

Molten salts is a promising medium for heat storage and heat transfer due to their advantages of low cost, low steam pressure, high energy storage density and wide temperature range. In this paper, a new phase change mixture of molten salts with KNO3, NaNO3, ZnCl2, NaF, Na2CO3, NaCl, and MgO as materials has been prepared through a plenty of experiments. The experimental results show that the melting point of some molten salts can be reduced to 202.9°C, and the decomposition temperature can reach 701.3°C. In addition, its thermophysical properties, including specific heat, viscosity and thermal stability, were measured and analyzed. The average specific heat of some molten salts is as high as 2.53 J/(g K), and the average thermal conductivity is as high as 0.77 W/(m K). In the 4-day short-term thermal stability test, the fluctuation of each parameter is minimal, and the overall thermal physical property is relatively stable. Compared with the traditional phase change molten salt, the new hybrid molten salt has a significantly lower melting point, a further improvement in the decomposition temperature, specific heat and other comprehensive thermophysical properties, and a better overall economy, which has important application value in heat transfer and energy storage. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials have been identified as promising candidates for future electronic devices. However, high dielectric constant (κ) materials, which can be integrated with 2D semiconductors, are still rare. Here, we report a hydrate-assisted thinning chemical vapor deposition (CVD) technique to grow manganese oxide (Mn3O4) single crystal nanosheets, enabled by a strategy to minimize the substrate lattice mismatch and control the growth kinetics. The material demonstrated a dielectric constant up to 135, an equivalent oxide thickness (EOT) as low as 0.8 nm, and a breakdown field strength (Ebd) exceeding 10 MV/cm. MoS2 field-effect transistors (FETs) integrated with Mn3O4 thin films through mechanical stacking method operate under low voltages (<1 V), achieving a near 108 Ion/Ioff ratio and a subthreshold swing (SS) as low as 84 mV/dec. The MoS2 FET exhibit nearly zero hysteresis (<2 mV/MV cm⁻¹) and a low drain-induced barrier lowering (~20 mV/V). This work further expands the family of 2D high-κ dielectric materials and provides a feasible exploration for the epitaxial growth of single-crystal thin films of non-layered materials. High dielectric constant (κ) materials compatible with van der Waals materials are desired to promote the development of 2D electronics. Here, the authors report a method to grow Mn3O4 nanosheets exhibiting κ up to 135 and equivalent oxide thickness down to 0.8 nm, enabling the fabrication of high-performance 2D MoS2 transistors. [ABSTRACT FROM AUTHOR]

Nickel silicon carbide (Ni-SiC) nanocomposite coatings are extensively used in the engineering field due to their exceptional mechanical characteristics. In this study, pulsed electrodeposition from a nickel Watts bath on a cast iron (CI) cylinder liner produced a Ni-SiC nanocomposite coating. The current study concentrated on multi-objective optimization to maximize microhardness and minimize surface roughness of the composite coating by grey relational analysis (GRA) and the contribution of coating parameters was analyzed by analysis of variance (ANOVA). The GRA-ANOVA-ANOVAt shows that the effects of the square term of duty cycle (Y2), the linear term of current density (Z), and the square term of frequency (X2) are most significant and affect the coating characteristics at a 95% confidence level. The inclusion of SiC particles altered the preferred coating crystallographic orientation from (200) to (111). The optimal coating parameters of frequency 100 Hz, duty cycle 80%, and current density 0.5 A/cm2 produced the best mechanical properties for Ni (79.38 wt%), Si (0.76 wt%), and C (19.86 wt%). According to the ANOVA, the linear term of current density (Z) and the quadratic terms of duty cycle (Y2) and frequency (X) have a significant influencing role with contributions of 27.74, 24.18, and 22.90%, respectively. EDX analysis of the Ni-SiC coating showed that carbon is the dominant element, comprising 54.52 wt. % and 19.86 wt. %, followed by nickel and silicon. [ABSTRACT FROM AUTHOR]

The electromagnetic frequency high-energy stir casting process was used to create the high-quality magnesium (Mg) dispersed with varied percentages of nano-sized B4C (0, 0.5, 1 and 1.5 wt%). The shape and distribution of Mg with nano B4C were validated by characterization research on nanocomposites utilizing energy-dispersive spectrum, scanning electron microscope and X-ray diffraction. Thermal and mechanical characteristics such as thermogravimetric analysis/differential thermal analysis and tensile strength were explored utilizing acoustic emission. During a tensile test, online monitoring using acoustic emission (AE) demonstrates a reduction in fracture development and propagation. The tensile test result exhibits that, Mg-1.5% B4C nanocomposite has a better tensile strength (σultimate = 125 MPa) than the Mg-0.5% B4C nanocomposite (σultimate = 115 MPa). AE results show that the hit begins at 26 µs for Mg-1.5% B4C nanocomposite, whereas for Mg-0.5% B4C nanocomposite, it begins at 14 µs. Thus, AE results show that an increase in B4C nanoparticles in the composites will prevent hits from occurring. The SEM and atomic force microscopy analyses were performed on the tensile-tested specimens to find the distinguishing characteristics. Owing to the inclusion of the B4C, the Mg-1.5% nano B4C composite has a longer ignition time in the thermogram of TGA and greater tensile strength than the Mg. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have garnered significant attention owing to their fluorescence properties and biocompatibility, especially red fluorescent CDs for bio-imaging and optoelectronics. However, existing red fluorescent carbon dots exhibit limitations regarding shorter red wavelengths, lower fluorescence intensities, and complex preparation procedures. This paper employed the microwave method to synthesize four water-soluble red fluorescent carbon dots, utilizing p-phenylenediamine and urea as precursors. By doping with manganese and adjusting the precursor concentration, we enhanced the intensity and the wavelength of red fluorescence under 365 nm UV light. The manganese-decorated carbon dots (Mn-CDs) showed a 32 nm redshift compared to the original carbon dots (O-CDs). The manganese-decorated/precursor concentration changed carbon dots (Mn/P-CDs) had four times higher intensity and 677 nm wavelength. The enhancement was mainly due to the increased nitrogen content from manganese addition and the decreased precursor concentration. We also synthesized composite polyfluorescent films with four CDs as pigments, exhibiting excellent transparency, flexibility, and luminescence in various media. Importantly, we demonstrated that their luminescent properties remained intact across multiple media. This study provides a valuable method for high-quality red CDs synthesis and a novel perspective for their applications. [ABSTRACT FROM AUTHOR]

Many ant species inhabit closed environments with limited spaces underground, encompassing a potential risk of pathogen reservoir and transmission among colony members. Despite accumulated research on the triggers of endemic outbreaks, the mechanism through which pathogenic microorganisms are introduced into ant colonies from outside the nest remains unclear. Waste materials could be one of the potential sources of pathogens, and we hypothesize that the feces of infected foragers may serve as a route of pathogen infiltration into the nest. In this study, we examined the transmission route and distribution pattern of an entomopathogenic bacterium, Pseudomonas entomophila, and ant behaviors in the nest using Diacamma cf. indicum from Japan. First, through infection experiments, we revealed that infected foragers introduce foreign pathogens into the nest via their feces, and the distribution of introduced pathogens within the nest shows a bias towards the midden room. Subsequently, our behavioral observations showed that reproductive individuals tend to remain in the other nest rooms. Overall, our results suggest that while the feces of infected foragers are potential reservoirs of disease outbreaks within a colony, such a risk might be mitigated by confining feces in a specific room of the ant nest. [ABSTRACT FROM AUTHOR]

A series of highly dispersed Nia-xMnxAlOy catalysts derived from layered double hydroxides (LDHs) were prepared for selective catalytic reduction of NOx with ammonia (NH3-SCR) at low temperature. The physicochemical and catalytic performance of the prepared catalysts with different M2+/M3+molar ratios were systematically investigated by XRD, BET, XPS, TPX (i.e. TPD and TPR) and in situ DRIFTs. Fortunately, Ni4-xMnxAlOy as the optimal catalyst exhibited prominent NH3-SCR performance with NOx conversion greater than 90% at low temperature range of 120~210 °C. Especially, the influence of H2O and SO2 revealed that the catalyst activity could be miraculously promoted by H2O, while deactivated by SO2. The proper M2+/M3+molar ratios not only provided the surface acidic sites, the high Mn4+ content ratio and the adsorbed oxygen of Nia-xMnxAlOy catalysts, but also promoted the transformation of NOx intermediate species to more stable bidentate nitrates. Results of the in situ DRIFTs illustrated that the SCR reaction path of Nia-xMnxAlOy catalysts followed both E-R and L-H mechanisms, and the former played the dominant role. [ABSTRACT FROM AUTHOR]

The mechanical material behavior of mild steels is reversible in the cooling phase of natural fires, which is proven by experimental evidence. For the material behavior of high-strength steels during cooling, no results are yet available. The paper provides the first comprehensive test program on the constitutive material behavior of high-strength steels S690QL and S960QL as well as mild steel S355 J2 + N in the case of natural fires. It is elaborated that the mechanical material behavior of high-strength steels in the cooling phase differs from the behavior in the heating phase and is not reversible due to phase changes of the microstructure. A constitutive material model for structural fire design purposes is developed on the basis of experimental data and the soundness and reliability of the model are proven by a statistical study that systematically evaluates the deviation of the model prediction from the test data. [ABSTRACT FROM AUTHOR]

A series of rare-earth (Ce, La, Nd, and Y) oxides doped Mn/Al2O3 catalysts were prepared by the impregnation method and used for the selective catalytic reduction (SCR) of NOx with NH3. The additions of rare-earth oxides greatly enhance the SCR catalytic activity of Mn/Al2O3, and the highest activity was obtained over CeMn/Al2O3 with a NOx conversion higher than 85% at 125–300 °C. The results of characterization show that the rare-earth oxides additives except for Y2O3 promote the surface distribution of Mn element and enhance the ratio of chemisorbed oxygen and Mn4+ on the surface of Mn/Al2O3. Moreover, with the introduction of rare-earth oxides, the reducibility of MnO2 species is improved and a larger amount of the weak acid sites are obtained. The increase in the ratio of Mn4+ and the enhancement in the reducibility of MnO2 are the main reasons for the elevation in SCR activity of the rare-earth oxides modified Mn/Al2O3 catalysts. This study sheds light on the promotional effect of rare-earth oxides over the Mn-based catalysts for SCR reaction. Rare-earth oxides greatly enhance the SCR catalytic activity of Mn/Al2O3, and the highest activity was obtained over CeMn/Al2O3 with a NOx conversion higher than 85% at 125–300 °C. [ABSTRACT FROM AUTHOR]

Manganese oxide octahedral molecular sieve (OMS-2) nano-rods were synthesized in the presence of HNO3 and then ion-exchanged with Ru3+ to obtain Ru-modified scaffolds abbreviated as Ru-OMS-2. Various techniques including X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), energy dispersive X-Ray spectroscopy (EDS), X-Ray photoelectron spectroscopy (XPS), and EDS mapping analysis were used to characterize the structure of the obtained product. Ru-OMS-2 was then used as a reusable heterogeneous catalyst in the selective oxidation of polycyclic aromatic hydrocarbons and heterocyclic compounds such as olanzapine and benzothiophene in an aqueous solution. Under mild reaction conditions, excellent yields of the desired products (10 examples, 55–99% yield) were obtained with high selectivity, and the catalyst retained activity for several consecutive cycles with a reasonable loss of activity (7.5% after 10 runs). [ABSTRACT FROM AUTHOR]

Manganese-based cathodes have been extensively studied as a promising option for aqueous zinc-ion batteries (AZIBs) due to their cost-effectiveness and elevated operational potential. However, the poor electrical conductivity, structural deterioration and manganese dissolution lead to limited ion/electron transfer rate and rapid capacity decay which cannot satisfy the practical applications of high energy density storage devices with long cycle lifespan and superior rate capability. Herein, an individual Mn2O3 nanoparticles self-assembled Mn2O3 nanofiber cathode was designed via electrospinning and subsequent calcination strategy. The phase and morphology structures can affect the electrochemical zinc storage performance by adjusting the annealing temperature. Benefitting from its unique structure, the Mn2O3-550 electrode exhibited predominantly capacitive-controlled zinc-ion storage behavior and enhanced electron and ion transfer kinetics, delivering a reversible capacity of ~ 228.8 mAh g–1 with a high loading mass of 2.0 ~ 2.5 mg cm−2. Furthermore, this innovative approach can be universally applied to create diverse Mn-based and V-based oxide materials featuring unique nanostructures, offering great potential for the development of high-performance energy storage device electrodes. [ABSTRACT FROM AUTHOR]

A novel cross-linked network structure of MnO2 nanotubes@Co3O4 polyhedron composite had been successfully prepared. Cobalt metal–organic framework (ZIF-67) in-situ grew on the open end of MnO2 nanotubes. Via a thermal treatment, MnO2@ZIF-67 was transformed into MnO2@Co3O4. When the Mn/Co molar ratio was 4:5, MnO2@Co3O4-45 showed excellent catalytic performance and water-resistance, which could obtain 100% HCHO conversion at 60 °C. The superior catalytic performance was mainly contributed to the strong synergistic interaction originated from the coupled interface between MnO2 and Co3O4. Moreover, the high percentage of Mn4+ and Co3+, plenty surface active oxygen species and well low-temperature reducibility played important roles for the enhancement of catalytic activity. DFT simulations showed that MnO2@Co3O4 exhibited the moderate adsorption capacity for HCHO, O2 and H2O, facilitating desorption of products and then continuing to the next catalytic reaction. Reaction pathways were also proposed under different atmosphere by in situ DRIFTS analysis. [ABSTRACT FROM AUTHOR]

In this paper, we employed a hydrothermal method to synthesize different ratios of NH2-MIL-125(Ti) modified manganese dioxide (MnO2@ NH2-MIL-125(Ti)) and explored the effect of pH and mass fraction on the degradation of Rhodamine B. The characterization (XRD, XPS, SEM) of the material proves that MnO2 successfully adheres and grows on the NH2-MIL-125(Ti) frameworks, changing the micromorphology while increasing the yield. In particular, when the NH2-MIL-125(Ti) is introduced at a ratio of 15%, the composite sample reveals optimal degradation performance, with a rate of Rhodamine B degradation as high as 95.8% in 40 min, which is about 1.6 times better than that of pure MnO2. And it can perform superior oxidation performance under acidic conditions. The increased active sites due to the introduction of the framework structure and the higher redox potential under acidic conditions are the main reasons for the improved oxidative properties. In addition, we put forward a mechanism of growth and oxidative degradation for the composite sample for this phenomenon. Highlights: A simple hydrothermal method is used to obtain the oxidant MnO2@ NH2-MIL-125(Ti). The sample MnO2@ NH2-MIL-125(Ti)-15% exhibits the optimum oxidation performance of 95.8% for RhB. The oxidation of the sample to RhB is augmented under acidic conditions (pH = 3). Propose growth mechanism of oxidant MnO2@ NH2-MIL-125(Ti) and degradation mechanism of RhB. [ABSTRACT FROM AUTHOR]

Evaluating drought is paramount in water resources management and drought mitigation plans. Drought indices are essential tools in this evaluation, which mainly depends on the time period of the original datasets. Investigating the effects of time periods is critical for a comprehensive understanding and evaluation of drought. Also, It holds particular significance for regions facing data availability challenges. The existing literature reveals a gap in drought assessment and comparison analysis using conventional methods based on drought indices only. This research proposes an innovative drought classification matrix to compare drought indices and spatial and temporal scenarios; the proposed matrix depends on any drought classification for comparison procedure. Furthermore, it aims to investigate the differences between several time period scenarios based on the proposed matrix and several statistical metrics (R2, CC, RMSE, HH, and RB) and determine the acceptable/minimum time period. The application of the proposed matrix and selection of an acceptable/minimum time period is presented to three different climates: Durham station in the United Kingdom, Florya station in Türkiye, and Karapinar station in Türkiye. The results show that the time period scenarios are able to catch the reference time period (RTP) scenario reasonably, with strong correlation and negative relative bias. The 10-year time period is sufficient as an acceptable/minimum time period for short timescales, such as meteorological drought. Conversely, for longer timescales, such as hydrological drought, a 20-year time period is the acceptable/minimum time period. The proposed matrix demonstrates a robust and powerful framework for comparison, making it applicable to various drought assessment scenarios globally. [ABSTRACT FROM AUTHOR]

Sustainable battery recycling is essential for achieving resource conservation and alleviating environmental issues. Many open/closed-loop strategies for critical metal recycling or direct recovery aim at a single component, and the reuse of mixed cathode materials is a significant challenge. To address this barrier, here we propose an upcycling strategy for spent LiFePO4 and Mn-rich cathodes by structural design and transition metal replacement, for which uses a green deep eutectic solvent to regenerate a high-voltage polyanionic cathode material. This process ensures the complete recycling of all the elements in mixed cathodes and the deep eutectic solvent can be reused. The regenerated LiFe0.5Mn0.5PO4 has an increased mean voltage (3.68 V versus Li/Li+) and energy density (559 Wh kg–1) compared with a commercial LiFePO4 (3.38 V and 524 Wh kg–1). The proposed upcycling strategy can expand at a gram-grade scale and was also applicable for LiFe0.5Mn0.5PO4 recovery, thus achieving a closed-loop recycling between the mixed spent cathodes and the next generation cathode materials. Techno-economic analysis shows that this strategy has potentially high environmental and economic benefits, while providing a sustainable approach for the value-added utilization of waste battery materials. Direct recycling of critical battery materials bring promise but a challenge for the mixed cathode chemistries. Here, the authors report a sustainable upcycling approach, transforming degraded LiFePO4 and Mn-rich cathodes into a high-voltage polyanionic material with an increased energy density and economic value. [ABSTRACT FROM AUTHOR]

Correct inflow prediction is a critical non-engineering measure for ensuring flood control and increasing water supply efficiency. In addition, accurate inflow prediction can offer reservoir planning and management guidance since inflow is the major input into reservoirs. This study aims at generalizing a machine learning model for forecasting reservoir inflow. Daily, weekly, and monthly inflow and rainfall time-series data have been collected as two hydrological parameters to forecast reservoir inflow using a machine learning method, namely, support vector regression (SVR). Four different SVR kernels have been applied in this study. The kernels are radial basis function (RBF), linear, normalized polynomial, and sigmoid. Two scenarios for input selection have been implemented. Dokan dam in Kurdistan region of Iraq and Warragamba Dam in Australia were selected as the case studies for this research. For the purpose of generalization, the proposed models have been applied to two countries with a different climate condition. The findings showed that daily timescale outperformed weekly and monthly, while RBF outperformed the other SVR kernels with root-mean-square error (RMSE) = 145.7 and coefficient of determination (R2) = 0.85 for forecasting daily inflow at Dokan dam. However, RBF kernel could not perform well for forecasting daily inflow in Warragamba dam. The results showed that the proposed machine learning model performed well at Kurdistan region of Iraq only, while the result for Australia was not accurate. Therefore, the proposed models could not be generalized. [ABSTRACT FROM AUTHOR]

Water quality is one of the most relevant issues related to water management, with water pollution and access to clean water for drinking and irrigation being common issues in developing countries. Groundwater is an available water source, especially where surface sources are scarce or unsuitable. In this sense, studies to improve knowledge of aquifers should be undertaken where information on groundwater resources is not available. In the current study, 50 groundwater samples were collected from rural and urban wells used by local communities for human consumption and to irrigate local crops. Several indices for drinking water and irrigation use have been used for the assessment of water quality. Conversely, the carcinogenic and noncarcinogenic human health risks due to exposure to heavy metals in the groundwater were estimated, as were the predominant hydrochemical characteristics. The groundwater water quality index (GWQI) shows values < 100 for all the samples; groundwater is recommended for drinking after disinfection. By contrast, the irrigation water quality index (IWQI) shows that 80% of groundwater samples pose a potential threat to irrigation, with restriction categories ranging from high to severe. The individual hazard quotients were < 1. However, the multielement and multipathway hazard index (HI) for children and adults were > 1, whereas As and Mn had a higher contribution to the HI. The Piper trilinear diagram shows that hydrochemical facies of Ca2+ and HCO3− are significantly dominant. By contrast, weathering of rocks and atmospheric precipitation is the dominant factors regulating the chemistry of groundwater in the aquifer system of La Mojana. Our findings indicate that there are significant potential noncarcinogenic health risks for local populations exposed to groundwater. [ABSTRACT FROM AUTHOR]

In this paper, MnOx/TiO2 catalysts with different manganese contents were prepared by using vacuum over-impregnation method to support manganese on TiO2 support. However, the activity temperature window was narrow and the denitrification efficiency was only 265–365 °C in the temperature zone above 80%. Therefore, doping W was used to improve the high temperature activity and broaden the activity temperature window. The experimental results show that the active temperature window of the catalyst is expanded to 260–550 °C when doping 20%WO3. The effects of tungsten doping on the structure and surface properties of the catalysts were investigated by XRD, TEM, Raman, XPS, H2-TPR and NH3-TPD. It is found that the increase of manganese content would increase the ratio of Mn4+ and Oα, and then improve the NH3-SCR activity at low temperature. Tungsten doping can provide more strong acid sites and improve the high temperature activity of the catalyst by inhibiting the oxidation of ammonia. [ABSTRACT FROM AUTHOR]

Purpose: Human exposure to particulate matter emitted from on-road motor vehicles includes complex mixtures of heavy metals from tyres, brakes, part wear, and resuspended road sediment. The purpose of this study was to determine the concentrations of 14 platinum-group and other traffic-related heavy metals in road sediment within the metropolitan area of Guangzhou, China, with a view to identifying their sources and assessing the extent of anthropogenic influence on heavy metal contamination of road sediment. Materials and methods: Thirty-five samples of road sediment were collected. The concentrations of Cr, Mn, Ni, Cu, Zn, La, Ce, Mo, Cd, Pb, Ba, and Rh were measured by inductively coupled plasma-mass spectrometry. Pt and Pd were analyzed by isotopic dilution-inductively coupled plasma-mass spectrometry. Multivariate statistical analysis and enrichment factor methods were employed to identify the sources of these heavy metals and to assess anthropogenic influences on their occurrence. Results and discussion: The mean concentrations of Pt, Pd, Rh, Cr, Mn, Ni, Cu, Zn, La, Ce, Mo, Cd, Pb, and Ba in the road sediment samples were 68.24, 93.15, 23.85, 147.5, 712.3, 47.24, 177.5, 1254, 47.50, 96.62, 4.91, 3.00, 198.1, and 641.3 ng g, respectively. Very weak to significant linear positive correlations were found among the various heavy metals. The elemental composition of road sediment was dominated by five principal components. Three clusters were identified through cluster analysis, and enrichment factors were calculated relative to soils in China. The sources and degree of contamination of the heavy metals are discussed based on the results. Conclusions: The mean concentrations of heavy metals are higher than background values, especially for Pt, Pd, Rh, Cd, and Zn. Four main sources are identified: (1) Pt, Pd, and Rh were derived from traffic sources; (2) La, Ce, Mn, and Ba were derived mainly from natural sources; (3) Cr, Ni, Cu, Mo, Cd, and Pb showed mixed traffic-industry sources; and (4) Zn originated mainly from industrial sources. Enrichment factor analysis supported this source identification and further indicated that contamination of road sediment in Guangzhou is extremely high for Pt, Pd, and Rh; moderate to very high for Cd, Zn, Pb, Cu, and Mo; and minimal for Cr, Ni, La, Ce, and Ba. [ABSTRACT FROM AUTHOR]

Cirrhotic cardiomyopathy is a myocardial disease that may go undetected in the early stages due to peripheral vasodilatation. The aim of the study was to evaluate the electrocardiogram (ECG) and heart rate variability (HRV) after raising blood pressure by phenylephrine injection in rats with liver cirrhosis. Twenty male Sprague–Dawley rats were divided into the Sham and common bile duct ligation (CBDL) groups. After 44 days, animals were anesthetized and the right femoral artery and vein catheterized. After a steady-state period, a bolus injection of phenylephrine (PHE, 10 μg/μl/IV, baroreflex maneuver) was followed by a slow injection of PHE (100 μg/ml/5 min/IV, sustained maneuver). Rapid and slow injections of PHE resulted in a greater increase in mean arterial pressure (MAP) and a weaker bradycardia response in the CBDL group than in the Sham group. ECG analysis showed increased QT, QTc, JT, and T peak to T end in the CBDL group, which remained unchanged after PHE injection. On the other hand, the parasympathetic indices of the HF band and RMSSD, and the sympathetic index of the LF band after PHE injection were lower in the CBDL group than in the Sham group. ECG data indicated prolonged ventricular depolarization and repolarization, independent of blood pressure levels in cirrhosis. On the other hand, after PHE injection, the parasympathetic and sympathetic components of HRV decreased, regardless of the duration of elevated blood pressure. We suggest that HRV analysis can provide a useful approach to assess cardiac dysfunction associated with elevated blood pressure in cirrhosis. [ABSTRACT FROM AUTHOR]

Inland saline water (ISW)-based Penaeus vannamei aquaculture system is an emerging field of fisheries, which came as a magic capsule to boost the overall agri-cum-aquacultural economy of many countries including India. The standardized technology for ISW-based P. vannamei culture includes ameliorating the culture water with K+-ion supplementation and amending Ca++/Mg++ ratio to 1:2–3, so as to simulate the natural seawater (NSW) equivalence, and replicating the NSW-culture parameters in the ISW system. However, for sustained growth and enhanced profitability, there was a need for formulation of ISW-specific culture parameters. In view of this, the present study was undertaken wherein P. vannamei seeds (post-larvae 8) were experimentally reared in ISW ponds with three different stocking densities (30, 45 and 60 PL8/m2) for a period of 75 and 110 days across two culture seasons followed by evaluation of growth and economic performances. Our study revealed highest mean weight (21.21–28.10 g), specific growth rate (8.75–6.22%) and survival percentage (92.93–90.34%) and lowest feed-conversion ratio (1.14–1.21) in the 30/m2 stocking group over the two respective seasons. The lower stocking density group also displayed maximum economic viability, recording benefit–cost ratio of 2.01 and net profit of 2.73 USD/Kg at 110 days. Further, in terms of profit sensitivity it ensures comfortable margins at any uncertain inflationary/deflationary scenarios. Thus, it can be inferred that at 30/m2 stocking density, the ISW-based P. vannamei culture can become a financially viable and sustainable aqua-venture for aspirant farmers, which have the potential to transform salt-degraded wasteland into profit-making asset. [ABSTRACT FROM AUTHOR]

In this work, Cu-Mn oxide catalysts supported on ZSM-5 zeolite (Cu7Mn3Ox/ZSM‑5) were modified by low-cost method of acid leaching and employed for the catalytic oxidation of toluene. For investigating the effect of acid modification on catalysts deeply, the prepared materials were characterized by N2 adsorption–desorption, XRD, SEM, H2-TPR, XPS, NH3-TPD, Py-IR and TG. In the decomposition of toluene, the citric acid modified Cu7Mn3Ox/ZSM‑5 exhibited excellent performance of toluene conversion and adsorption compared to Cu7Mn3Ox/ZSM‑5. The preferable performance was associated with the improved pore structure and surface area, along with the more Mn4+ and Cu2+ species formed after citric acid modification. Significantly, citric acid modified Cu7Mn3Ox/ZSM‑5 exhibited satisfied hydrothermal stability and good regeneration ability as well, which would offer an economical strategy to prepare effective catalysts for VOCs treatment. [ABSTRACT FROM AUTHOR]

In this study, a CuO modified the MnO2 nano-hollow spheres sorbent was prepared using the impregnation method. The effects of the CuO loading amount, reaction temperature, gas hourly space velocity, and flue gas component on the Hg0 removal performance of the sorbent were investigated. When loaded with 10% CuO, the sorbent's Hg0 removal efficiency was higher than 95% from 150 to 250 °C. The combination of plentiful acid sites and superior redox behavior ensured the efficient adsorption and oxidation of Hg0, which endowed the 10% CuO-doped sorbent with a satisfactory Hg0 removal performance over a wide temperature range. Throughout the Hg0 capture cycles, the Mars–Maessen mechanism well-depicted the Hg0 removal process over the 10% Cu/Mn adsorbent, the Mn4+, Cu2+, and chemisorbed oxygen acted as the active sites with HgO being the end product. However, the weak flue gas component adaptability demonstrated that further modification is needed to enhance the practicality of this system. [ABSTRACT FROM AUTHOR]

Novel functional materials with competing degrees of freedom have potential breakthrough in the research and development of memory devices and spintronics. In this perspective, double perovskite provides flexible selection of cations and invoke keen interest for technological applications. In this report rare earth oxide material, Nd2FeMnO6 double perovskite have been investigated. Nd2FeMnO6 double perovskite was conventionally synthesized via solid state reaction method followed by sintering at high temperature of 1200 °C. Rietveld refined X-ray diffractograms establish the crystallization of the Nd2FeMnO6 system to be orthorhombic distorted structure having Pbnm space group and Fe/Mn cations being randomly arranged at B and B’ sites in the oxygen octahedra. The vibrational modes corresponding to the Fe and Mn cations in the Raman study substantiate the blending of NdMnO3 and NdFeO3 sublattices in Nd2FeMnO6 double perovskite. XPS measurement evidence the oxidation state of Fe and Mn ions in the oxygen octahedra to be + 3. Magnetic studies reveal room temperature antiferromagnetic ordering in Nd2FeMnO6 with a Neel transition at 505 K, are attributed to the Fe3+–O–Mn3+ and Mn3+–O–Mn3+ exchange integral chains. Low temperature ZFC/FC curves mark the appearance of thermomagnetic irreversibility at 90 K caused by the magnetic anisotropy of Jahn-Teller Mn3+ cations. Dielectric studies disclose an abrupt change in the dielectric constant at the vicinity of the Neel temperature for all measured frequencies, evidencing the existence of magnetodielectricity in Nd2FeMnO6 double perovskite. [ABSTRACT FROM AUTHOR]

A large amount of open-dumped electrolytic manganese residue (EMR) has posed a severe threat to the ecosystem and public health due to the leaching of ammonia (NH4+) and manganese (Mn). In this study, CaO addition coupled with low-temperature roasting was applied for the treatment of EMR. The effects of roasting temperature, roasting time, CaO-EMR mass ratio and solid–liquid ratio were investigated. The most cost-effective and practically viable condition was explored through response surface methodology. At a CaO: EMR ratio of 1:16.7, after roasting at 187 °C for 60 min, the leaching concentrations of NH4+ and Mn dropped to 10.18 mg/L and 1.05 mg/L, respectively, below their discharge standards. In addition, the magnesium hazard (MH) of EMR, which was often neglected, was studied. After treatment, the MH of the EMR leachate was reduced from 60 to 37. Mechanism analysis reveals that roasting can promote NH4+ to escape as NH3 and convert dihydrate gypsum to hemihydrate gypsum. Mn2+ and Mg2+ were mainly solidified as MnO2 and Mg(OH)2, respectively. This study proposes an efficient and low-cost approach for the treatment of EMR and provides valuable information for its practical application. [ABSTRACT FROM AUTHOR]

This study aimed to develop an ensemble machine learning (ML) model for multi-step ahead SSL modeling in the Katar catchment, Ethiopia. To do so, different ML models such as multilinear regression (MLR), Feed-forward Neural Network (FFNN), Support Vector Regression and Adaptive Neuro-Fuzzy Inference System (ANFIS) were applied for one, two and three-step ahead SSL modeling. For this, two years of daily discharge and SSL data were used for model calibration and validation. Finally, four ensemble techniques: neuro-fuzzy ensemble (NFE), neural network ensemble (NE), weighted average ensemble (WE) and simple average ensemble (SE), were developed to improve the performance of single models. The performance of the developed models was evaluated using percent bias (PBIAS), mean absolute error (MAE), root mean square error (RMSE) and Nash Sutcliffe Efficiency Coefficient (NSE). The result shows that ANFIS outperformed the other individual models with a validation phase NSE value of 0.916,0.9 and 0.88 and RMSE value of 1630.5 ton/day, 1850.6 ton/day and 2026.6 ton/day, for one, two and three steps-ahead predictions, respectively. The NFE technique improved the individual model's performance in the validation phase up to 42.17%, 49.84% and 60.66% for one, two and three-step ahead modeling. Generally, the use of ensemble techniques resulted in promising improvements in single and multi-step ahead SSL modeling. [ABSTRACT FROM AUTHOR]

The diagnosis of long COVID is troublesome, even when functional limitations are present. Dynapenia is the loss of muscle strength and power production that is not caused by neurologic or muscular diseases, being mostly associated with changes in neurologic function and/or the intrinsic force-generating properties of skeletal muscle, which altogether, may partially explain the limitations seen in long COVID. This study aimed to identify the distribution and possible associations of dynapenia with functional assessments in patients with long COVID. A total of 113 patients with COVID-19 were evaluated by functional assessment 120 days post-acute severe disease. Body composition, respiratory muscle strength, spirometry, six-minute walk test (6MWT, meters), and hand-grip strength (HGS, Kilogram-force) were assessed. Dynapenia was defined as HGS < 30 Kgf (men), and < 20 Kgf (women). Twenty-five (22%) participants were dynapenic, presenting lower muscle mass (p < 0.001), worse forced expiratory volume in the first second (FEV1) (p = 0.0001), lower forced vital capacity (p < 0.001), and inspiratory (p = 0.007) and expiratory (p = 0.002) peek pressures, as well as worse 6MWT performance (p < 0.001). Dynapenia, independently of age, was associated with worse FEV1, maximal expiratory pressure (MEP), and 6MWT, (p < 0.001) outcomes. Patients with dynapenia had higher intensive care unit (ICU) admission rates (p = 0.01) and need for invasive mechanical ventilation (p = 0.007) during hospitalization. The HGS is a simple, reliable, and low-cost measurement that can be performed in outpatient clinics in low- and middle-income countries. Thus, HGS may be used as a proxy indicator of functional impairment in this population. [ABSTRACT FROM AUTHOR]

Methylene blue is widely used in various industries. The discharge of industrial effluents with methylene blue residues may have hazardous effects on living systems. In this paper, the low-cost, eco-friendly, and abundant geoadsorbent natural manganese ore sand was used as an attractive material to remove methylene blue. The results indicated that the poorly crystalline manganese ore sand could simultaneously adsorb and degrade methylene blue. The pseudo-first-order and MnOII (I) kinetic models could describe the decolorization, but the latter had better predictive characteristics. The kinetics were affected by coexisting substances, but a decolorization efficiency of greater than 80% still could be achieved in actual water matrices. Characterization of manganese ore sand before and after use indicated that the degradation processes that occurred at pH values of 2, 3, 5, 7, and 10 included direct and indirect redox reactions. Specifically, the manganese ore sand behaved primarily as an oxidant at acidic pH, as a catalyst at alkaline pH, and simultaneously as oxidant and catalyst at a neutral pH. Possible degradation routes were proposed based on the suggested intermediates. The main behavior of the oxidant was demethylation of C–CH3 from methylene blue, and the degree of demethylation increased with decreased pH. As the catalyst, the C–N and C–S bonds on the central heterocycle could be further broken by manganese ore sand after demethylation. The performance of manganese ore sand is related to the content of high-valent Mn species. [ABSTRACT FROM AUTHOR]

On October 11 and November 3, 2018, two large landslides occurred at the same location in Baige Village, eastern Tibet, China. These landslides pose a serious threat to both upstream and downstream areas, raising great concerns in China and worldwide. Currently, the influencing factors and fundamental mechanism of the Baige landslide are questioned, and further research is needed. Multiple methods, including comprehensive field investigation, satellite remote sensing, unmanned aerial vehicle (UAV) 3D imaging, and geographical information systems, are used to analyze the main characteristics, influencing factors, and fundamental mechanism of the Baige landslide. The results reveal that the occurrence of the Baige landslide is closely related to deep-seated gravitational slope deformations (DSGSDs); tectonic activity, river incision, earthquakes, and rainfall are also responsible for the formation of the event. From a long-term perspective, DSGSDs, active tectonic deformation, repetitive seismic activities, rapid river incision, and sustained rainfall infiltration all interact with each other and finally trigger catastrophic landslides. The damage deformation process of the Baige landslide can be divided into three stages: epigenetic deformation, time-dependent deformation, and failure. Some unstable rock masses still exist in the source area, and thus, successive deformation monitoring and timely mitigation measures should be implemented to reduce the residual risks. The research in this paper is meaningful for further research on such large-scale landslides along the Jinsha River. [ABSTRACT FROM AUTHOR]

The design of the gas distribution for small-demand power plants located on remote islands is logistically challenging. The use of small-scale liquefied natural gas (LNG) vessels can be an option for these logistic problems. This paper aims to conduct a techno-economic analysis of using small-scale LNG vessels for gas distribution to the power plants that are spread across different islands. Route optimisation has been conducted using the capacitated vehicle routing problem method. The ship's principal dimensions were determined using the aspect ratio from a linear regression of existing small-scale LNG vessels. As a case study, the gas demands for a gas power plant in eastern Indonesia were analysed into four distribution clusters. The results of the techno-economic analysis showed that the four distribution clusters have different characteristics regarding the LNG requirements, location characteristics and ship specifications. The capacity of small-scale LNG vessels feasible in terms of technical aspects varies from 2500, 5000, to > 10,000 m3 with variations in the ship speed depending on the location of the power plants. The amount of cargo requested and the shipping distance was affected to the cost of LNG transportation. The economic assessment proposes that the feasible investment by considering small-scale LNG cargo distribution, from the case study shows that with a ship capacity of 5000 m3 feasible margin rate is ≥ 3 USD/metric million British thermal units with an internal rate of return of 10% and estimated payback period is less than 15 years. [ABSTRACT FROM AUTHOR]

The hydrolysis-driven redox co-precipitation method was employed to initiate the reduction of KMnO4 by H2O2, facilitated by the generation of H+ through the hydrolysis of cobalt salts. This controlled redox kinetics resulted in the formation of a Co–Mn solid solution catalyst, which exhibited high efficiency in the catalytic oxidation of toluene. T90 (the reaction temperature corresponding to a conversion of 90%) was only 214°C, at toluene concentration of 1000 ppm and weight hourly space velocity (WHSV) of 36 000 mL g–1 h–1. Moreover, the conversion of toluene was still more than 98% with a continuous reaction of 77 h at 260°C. Additionally, the conversion of toluene remained above 98% even after 4 h of 1,2-dichloroethane poisoning reaction at 260°C, indicating that the Co1Mn2 catalyst exhibited both high activity and resistance to toxicity. [ABSTRACT FROM AUTHOR]

In senescent leaves of higher plants, colourless chlorophyll (Chl) catabolites typically accumulate temporarily, and undergo natural oxidation, in part, to yellow- and pink-coloured phyllobilins (PBs). The latter, also classified as phylloroseobilins (PrBs), represent the final currently established products of Chl-breakdown, possibly playing important roles in metabolism. However, PrBs, themselves, do not accumulate in the leaves. Indeed, the original PrB identified, then classified as a pink Chl-catabolite (PiCC), is remarkably instable in methanolic solution. As reported here, PiCC readily converts at room temperature into yellow tetrapyrroles. The deduced main process, a retro-Dieckmann reaction, cleaves open its ring E moiety, the α-methoxycarbonyl-cyclopentanone unit characteristic of the Chls and of the natural Chl-derived PBs. This readily occurring reaction of the PiCC represents an unprecedented skeletal transformation of a PB, furnishing a cross-conjugated biladiene with a basic structure more similar to the heme-derived bilins. [ABSTRACT FROM AUTHOR]

Mine tailings are one of the primary contaminant sources of heavy metals and metalloids in the soil. Besides increasing the concentration of potentially toxic elements (PTEs), tailings may modify the edaphic conditions and decrease the buffer capacity of impacted soils. The influence of tailings may reach distances far from the impoundments depending on the transport path and the specific transport mean: air, rain (runoff and infiltration), or acid mine drainage. In this study, soil samples from various horizons were collected in trial pits along a transect, at different distances from sulfide tailings. Soil analysis included texture, organic matter, alkalinity, porous space, carbonates, pH, electrical conductivity, real density, apparent density, total sulfur, main mineralogy, and total concentrations of As, Cd, Pb, Fe, and Zn. Graphical and statistical interpretation of the results showed that real density and porous space are the leading indicators of the tailings dispersion and accumulation and that pH is not a significant parameter (all values were above the neutrality) due to the limestone abundance in the area. However, Zn and Cd concentrations had an inverse relation with pH. Differences in the concentrations of PTEs between the superficial and deep layers that increased toward the tailings were also observed. Gypsum was only present in the closest samples to the tailings and may also be an indicator of tailings' influence on soils. This study allowed us to identify general edaphic parameters as a first and quick means to determine the tailings contamination of soils. [ABSTRACT FROM AUTHOR]

Background: Orthostatic hypotension (OH) is a potential modifiable risk factor for cognitive impairment in patients with Parkinson's disease (PD). Although other risk factors for dementia, hyposmia and REM sleep behavior disorder (RBD), are closely associated with autonomic dysfunction in PD, little is known about how these risk factors influence cognitive function and cerebral pathology. Objective: We investigated how these three factors contribute to gray matter atrophy by considering the interaction of OH with hyposmia and RBD. Methods: We analyzed cortical thickness, subcortical gray matter volume, and cognitive measures from 78 patients with de novo PD who underwent the head-up tilt test for the diagnosis of OH. Results: Whole-brain analyses with Monte Carlo corrections revealed that hyposmia was associated with decreased cortical thickness in a marginal branch of the cingulate sulcus among patients with OH, and cortical thickness in this area correlated with cognitive functioning only in patients with OH. Subcortical gray matter volume analysis indicated that severe RBD was associated with decreased volume in the left hippocampus and bilateral amygdala among patients with OH. Conclusion: Even in early PD, OH exerts effects on gray matter atrophy and cognitive dysfunction by interacting with RBD and hyposmia. OH might exacerbate cerebral pathology induced by hyposmia or RBD. [ABSTRACT FROM AUTHOR]

A process for fabricating Zn-doped (up to 10 at %) β-Ga2O3 thin films by plasma-enhanced chemical vapor deposition has been studied. High-purity gallium, zinc, and oxygen were used as starting materials, and hydrogen was chosen as the carrier and plasma gas. A low-temperature nonequilibrium RF (40.68 MHz) discharge plasma at a reduced pressure (0.01 torr) was used to initiate chemical reactions of precursors. The plasma-chemical process was monitored using optical emission spectroscopy. Structural properties and morphology of the deposited β-Ga2O3 films were studied by various methods. [ABSTRACT FROM AUTHOR]

Highlights: Oxygen-coordinated single-atom Mn catalyst was fabricated via introducing oxygen functional groups rich bacterial cellulose as the adsorption regulator through a combined impregnation–pyrolysis–etching synthetic route. Mn–O–C as the electrocatalyst exhibits superior electrocatalytic activity toward ammonia synthesis with a maximum NH3 yield rate of 1476.9 ± 62.6 μg h−1 cm−2 at − 0.7 V (vs. RHE) and a faradaic efficiency of 89.0 ± 3.8% at − 0.5 V (vs. RHE) under ambient conditions. Electrocatalytic mechanism of Mn–(O–C2)4 site for nitrate reduction reaction is unveiled by a combination of in situ spectroscopy characterization and computational study. Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection. Here, we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen (O) coordination on bacterial cellulose-converted graphitic carbon (Mn–O–C). Evidence of the atomically dispersed Mn–(O–C2)4 moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy. As a result, the as-synthesized Mn–O–C catalyst exhibits superior NitRR activity with an NH3 yield rate (RNH3) of 1476.9 ± 62.6 μg h−1 cm−2 at − 0.7 V (vs. reversible hydrogen electrode, RHE) and a faradaic efficiency (FE) of 89.0 ± 3.8% at − 0.5 V (vs. RHE) under ambient conditions. Further, when evaluated with a practical flow cell, Mn–O–C shows a high RNH3 of 3706.7 ± 552.0 μg h−1 cm−2 at a current density of 100 mA cm−2, 2.5 times of that in the H cell. The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn–(O–C2)4 sites not only effectively inhibit the competitive hydrogen evolution reaction, but also greatly promote the adsorption and activation of nitrate (NO3−), thus boosting both the FE and selectivity of NH3 over Mn–(O–C2)4 sites. [ABSTRACT FROM AUTHOR]

In order to design and establish a highly efficient and selective nanozyme-based sensing platform for the UV-vis detection of organophosphorus pesticides (OPs), Mn was introduced into ZIF-8 nanozyme for enhancing its catalytic activities and adding specific recognizer. The Mn-doped ZIF-8 (Mn-ZIF-8) nanocomposites were synthesized with a very facile one-pot method by heating the mixture of ZnO, 2-methylimidazole (Hmin) and Mn(CH3COO)2·4H2O in a solvent-free system at 180 °C for 8 h. The Mn-ZIF-8 nanocomposite showed a higher peroxidase activity and an additional thiocholine (TCh)-degradable property compared to the pristine ZIF-8. OPs could inhibit acetylcholinesterase (AChE) to catalyze the hydrolysis of acetylthiocholine (ATCh) to produce TCh, thus blocking the degradation of Mn-ZIF-8 and protecting the catalysis of the oxidation of colorless 3,3′,5,5′-tetramethylbenzydine (TMB) to blue oxidized TMB (ox-TMB). Accordingly, a detection method for OPs with high sensitivity and selectivity was designed and established on the basis of the Mn-ZIF-8 nanozyme with a linear range of 0.1–20 nM and a limit of detection (LOD) as low as 54 pM. [ABSTRACT FROM AUTHOR]

The effects of the two materials, Ti3C2-CQDs and Na3V2(PO4)2F3, on the electrochemical properties of Na2MnPO4F were systematically investigated by double modification of Na2MnPO4F by spray drying method combined with high-temperature calcination. Firstly, different ratios of xNa2MnPO4F-(1-x)Na3V2(PO4)2F3 materials were synthesized and discussed to obtain 0.6Na2MnPO4F-0.4Na3V2(PO4)2F3 material as optimal ratio. Ti3C2-CQDs were added on this basis, and electrochemical tests were performed at the same time. The initial discharge-specific capacity of 0.6Na2MnPO4F-0.4Na3V2(PO4)2F3/Ti3C2-CQDs was 137.4 mAh-g−1, indicating that Ti3C2-CQDs can improve the electronic conductivity as well as the ion diffusion rate of the material and the capacity retention rate. Na3V2(PO4)2F3 can effectively inhibit the Jahn–Teller effect, enhance the stability of the material structure, and improve the electrochemical activity of the material. The synergistic modification leads to a double enhancement of the electrochemical performance of Na2MnPO4F. It hopes that the findings can provide ideas for improving the electrochemical properties of polyionic compounds. [ABSTRACT FROM AUTHOR]

Because logistics companies usually have multiple depots to serve their many dispersed customers, multi-depot vehicle routing problem (MDVRP) has gained significant research attention. To solve an MDVRP model, this paper develops a hybrid ant colony optimization based on a polygonal circumcenter (BPC-HACO). Furthermore, because ACO has been found to fall easily into the local optimum, simulated annealing and three local optimization operations are introduced to encourage the ACO to improve the algorithm's optimization ability. Finally, MDVRP benchmarks and data sets of other papers are employed to verify the effectiveness of the BPC-HACO in solving MDVRP (In 23 instances, BPC-HACO finds 14 BSKs, and 3 results are better than the BSKs), MDVRP with distance constraints (Compared to other papers, the route length is reduced by an average of 17.94%) and dynamic MDVRP (In 10 instances, BPC-HACO finds 3 BSKs, and 2 results are better than the BSKs). Finally, fitness landscape analysis has been applied to analyze the structural features of MDVRP to choose the most appropriate algorithm for MDVRP. [ABSTRACT FROM AUTHOR]

A process for fabricating Al-doped β-Ga2O3 thin films of the (AlxGa1−x)2O3 composition by plasma-enhanced chemical vapor deposition has been studied for the first time. High-purity gallium metal, aluminum iodide (AlI3), and high-purity oxygen were used as precursors. Low-temperature plasma at a reduced pressure (0.01 torr) was the initiator of chemical transformations between the reactants. The plasma-enhanced deposition process was studied by optical emission spectroscopy in the range of 180–1100 nm. The obtained thin films of the (AlxGa1−x)2O3 system with the amount of the Al2O3 phase up to 20% were studied by various analytical methods. [ABSTRACT FROM AUTHOR]

The wastewater discharged from crude oil storage tanks (WCOST) contains high concentrations of salt and metal iron ions, and high chemical oxygen demand (COD). It belongs to "3-high" wastewater, which is difficult for purification. In this study, WCOST treatments were comparatively investigated via an advanced pretreatment and the traditional coagulation–microfiltration (CMF) processes. After WCOST was purified through the conventional CMF process, fouling occurred in the microfiltration (MF) membrane, which is rather harmful to the following reverse osmosis (RO) membrane unit, and the effluent featured high COD and UV254 values. The analysis confirmed that the MF fouling was due to the oxidation of ferrous ions, and the high COD and UV254 values were mainly attributable to the organic compounds with small molecular sizes, including aromatic-like and fulvic-like compounds. After the pretreatment of the advanced process consisting of aeration, manganese sand filtration, and activated carbon adsorption in combination with CMF process, the removal efficiencies of organic matter and total iron ions reached 97.3% and 99.8%, respectively. All the water indexes of the effluent, after treatment by the advanced multi-unit process, meet well the corresponding standard. The advanced pretreatment process reported herein displayed a great potential for alleviating the MF membrane fouling and enhanced the lifetime of the RO membrane system in the 3-high WCOST treatment. [ABSTRACT FROM AUTHOR]

Mn/TiO2, Mn-Ce/TiO2, and Sb-modified Mn-Ce-Sbx/TiO2 catalysts were prepared by the impregnation method. The catalysts were characterized by BET, XRD, XPS, SEM, NH3-TPD, FTIR, TG-DSC, H2-TPR, and the SCR (Selective Catalytic Reduction) activity, and investigated by SO2, and H2O resistance between 90 °C and 220 °C. Results showed that the molar ratio of Sb/Mn is 0.2, the catalytic activity of Mn-Ce-Sb0.2/TiO2 can reach 94% of NO conversion rate at 120 °C. Meanwhile, Mn-Ce-Sb0.2/TiO2 has the best SO2 and H2O resistance. Characterization results demonstrated that the modification of Sb can decrease the crystallinity of the Mn element, while Sb can inhibit the formation of sulfate and reduce the poisonous effect of SO2 on the catalyst. [ABSTRACT FROM AUTHOR]